<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .d1{
            color: red;
            font-size: x-large;
            font-weight: 800;
        }
    </style>
</head>
<body>
<div class="d1">你好</div> 
<script>

</script>   
</body>
</html>